**2. Classification and toxicity of pesticides**

Pesticides have a great variety of chemical structures, with diverse action mechanisms and applications. Nowadays, pesticides are presented in a large range of commercially products, with above 800 active components, belonging to more than 100 classes.

Pesticides can be classified bases on the pest type (A) and the origin (B) (**Figure 1**). In the first group of pesticides (A) are included: (1) herbicides, substances used to manage unwanted plant growth or to destroy weeds; (2) insecticides, used to kill infesting insects; (3) fungicides, used to control the propagation of fungi; (4) rodenticides that kill rodents; and (5) nematicides which kill nematodes or adversely affect nematodes. In the second group (B), pesticides can be categorized as chemical (synthetic) and biopesticides (biological or biorationals). The most outspread groups of pesticides are organochlorines, carbamates, pyrethroids and organophosphates. Organochlorines are the first important synthetic organic pesticides that belongs to the class of persistent organic pollutants (POPs). Biopesticides can be separated into two classes, that are, biochemical (hormones, enzymes, pheromones, natural insects, etc.) and microbial (viruses, bacteria, fungi, etc.).

Another classification of pesticides is based on the mode of action or mode of entry. Based on this, pesticides can be differentiated as non systemic, systemic, stomach poison, broad spectrum, disinfectant, nonselective, nerve poison, protectants and repellents. Moreover, pesticides can be classified using their acute toxicity.

**Figure 1.** *Classification of pesticides.*

WHO [13] grouped them in Class Ia = extremely hazardous, Class Ib = highly hazardous, Class II = moderately hazardous, Class III = Slightly hazardous, and Class U=Unlikely to present acute hazards.

Organochlorines (OCs) were among the frequently used pesticides in agriculture, and presented a high toxicity, with hazardous and bio-accumulation properties [14]. These types of pesticides are carcinogenic, persistent in the cycle of environmental degradation, belonging to group of chlorinated hydrocarbons. Moreover, they have high lipophilicity, low polarity and solubility in aqueous medium. OCs are forbidden and no longer used for agriculture in Europe, America and other countries. Organochlorines were substituted with other synthetic compounds such as carbamates, pyrethroids and organophosphorus. These synthetic compounds have a low price, low persistence in nature, high capacity to eliminate a vast number of pests.

The organophosphates and carbamates lead to disturbance in the normal functioning of the central nervous system (CNS), inhibiting the enzyme acetylcholinesterase (AChE) in (CNS) of humans and insects [15]. Organophosphates are widespread contaminants and are correlated with important toxicological threats to the soil, aquatic ecosystems and human health [16].

Pyrethroids are obtained from natural chrysanthemum ester containing natural chemicals, name as pyrethrins [17]. The synthetic pyrethroids have a longer environmental stability and half-life when as compared to the natural form. They have a particular insecticidal activity with reduced toxicity, operation by lagging the voltage gated sodium channel in the neuronal membrane.

Use of such pesticides in modern agriculture is regarded as beneficial for pest control, although residues accumulated in raw products or beverages are extremely dangerous to both human health and the environment. Consumption of wines that may contain residues of pesticides has a strong impact on human health, and may cause muscle weakness, respiratory disorder, paralysis, cancer, etc. [18, 19].

*Management of Pesticides from Vineyard to Wines: Focus on Wine Safety and Pesticides Removal… DOI: http://dx.doi.org/10.5772/intechopen.98991*
